WASHINGTON?Human rights groups have urged WikiLeaks to redact names of Afghans helping American forces from thousands of leaked US military documents, leading to a charged retort from the website's founder, the Wall Street Journal said Tuesday.

"We have seen the negative, sometimes deadly ramifications for those Afghans identified as working for or sympathizing with international forces," said a letter to WikiLeaks founder Julian Assange, according to the Journal, citing a person close to the exchange.

"We strongly urge your volunteers and staff to analyze all documents to ensure that those containing identifying information are taken down or redacted," said the letter from Amnesty International, Campaign for Innocent Victims in Conflict, Open Society Institute, Afghanistan Independent Human Rights Commission and International Crisis Group.

The message prompted Assange to question what the groups were themselves doing to examine the 70,000 classified documents on Afghanistan, which were published by WikiLeaks in late July, and whether they would be willing to help with the redaction process, the daily said.

The files contained a string of damaging claims, and included the names of some Afghan informants, leading to claims that the leaks have endangered lives.

Amnesty suggested they may be able to provide some resources to analyze the documents and some 15,000 other files that WikiLeaks is planning to release, and that Assange and the rights groups discuss the issue on a conference call.

"I'm very busy and have no time to deal with people who prefer to do nothing but cover their asses," Assange was reported to have replied.

"If Amnesty does nothing I shall issue a press release highlighting its refusal," he said, according to the Journal.

On its Twitter page, Wikileaks posted the update on August 8: "Pentagon wants to bankrupt us by refusing to assist review. Media won't take responsibility. Amnesty won't. What to do?"

Assange, 39, an Australian former hacker and computer programmer, has said he believed the publication would help focus public debate on the war in Afghanistan and on possible atrocities by US-led forces.

US Defense Secretary Robert Gates and Chairman of the Joint Chiefs of Staff, Admiral Mike Mullen, have however insisted the move endangered locals providing information to US-led NATO forces in Afghanistan.

WikiLeaks has never identified the source of the Afghan files, but suspicion has fallen on Bradley Manning, a US Army intelligence analyst under arrest for allegedly leaking video footage of a 2007 US Apache helicopter strike in Baghdad in which civilians died.

Manning is being held in a US military jail after being transferred from a US military base in Kuwait.

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